Joanie Diggs has put together an excellent tutorial on installing Ubuntu
with speech at: http://live.gnome.org/Orca/UbuntuEdgyEft Quick summary:
press a few keystrokes at the LiveCD splash screen (when the CD stops
whirring/spinning), and then do the install invoked as root from the
command-line (rather than via the GUI). It is a little more cumbersome
than what non-speech users need - and the problems preventing it being
more smooth are being worked on.